I hate my girlfriend

Occasionally me and her have a good time together but the majority of the time she puts me in a bad mood and is a complete fucking asshole to me.THe majority of weekends I end up home at 11:30 because my friends go to hang out with this group of girls that "I'm not allowed to be around" (because the girl I cheated on her with a while ago is in that group.)and I can't stand being with her friends, they are cunty. Its obvious thatif I feel like this I should break up with her but I am such a bitch. I crushed her 5 months ago when I hooked up with some girl at a party, I don't want to do that to her again. Should I stick it out and hope it gets better, talk to her, or just find a way out?